11 Dec
2012
11 Dec
'12
11:55 a.m.
On Dec 11, 2012, at 2:00 PM, John Wilson wrote:
On Tue, Dec 11, 2012 at 10:42:13AM -0800, Guy
Sotomayor wrote:
I might be persuaded to buy a few for characterization purposes (I'll
let you know off-list if that's the case), but I'm curious to know if
you're working on a RoHS/modern replacement. I'm currently prototyping
a board using comparators for the receivers and discrete FETs for the
drivers (no ICs I could find had compatible slew rate, capacitance and
drive strength with DEC's specs), but I'd be curious to know if you'd
found anything better. If not, I'll be glad to share my results (with
everyone) once I actually get the time to finish the prototype.
In any case, a modern replacement is likely to cost somewhat less per
pin than $1 in any realistic quantity, and will probably beat $.625
per pin (at the cost of some board real estate, which for a modern
PLD-based implementation shouldn't be an issue).
- Dave
I just thought that I'd let folks know that I
scored a bit (ok quite a bit) of
unobtainium in the form of Unibus receivers and transceivers.
In case anyone cares, I have DS3862Ns out the wazoo that I'd sell to anyone at
my cost ($5/ea) in any qty. These are basically a 20-pin 74LS245-like variant
of the DS8641N (so it does 8 bits instead of 4, with a direction control for
all 8 so you can't do things one bit at a time like with the DS8641N but you
get twice as many bits for only four extra pins). Specs supposedly improved
from the DS8641N but I forget in what way (slew rate limited?). I (i.e. D Bit)
bought a lifetime supply (2,000) back when they were being EOLed but then RoHS
happened and I won't be using them after all.